Editor / Map / Use main context to have a better default on new extent (geonetwork#8046)

The map configuration was not using a context and the map extent was centered on coordinate 0 0.

Use the default map context which will center on the context map extent which depends on each catalogue configuration.

Author: fxprunayre

web-ui/src/main/resources/catalog/js/CatController.js

@@ -845,9 +845,9 @@
               geodesicExtents: false
             },
             "map-editor": {
-              context: "",
+              context: "../../map/config-viewer.xml",
               extent: [0, 0, 0, 0],
-              layers: [{ type: "osm" }]
+              layers: []
             },
             "map-thumbnail": {
               context: "../../map/config-viewer.xml",